Cah/f)teratae and Acah/pteratae, Calypta and Calyptra. 329 



Tliis division was not equivalent to the Calypteratae of latcr 

 authors, because it did not include the Anthomyidae. R.-D. seems 

 to have been aware that the size of the squamae did not afford a 

 trönchant character for a subdivision of the Muscidae, and for this 

 reason he called his second family (gens) Mesomydae, on account 

 of their interniediate position (R.-D. 1830, p. 469, at bottom). 



Neither the division Acalypterata, nor its name oc- 

 curs in R.-D.'s quarto of 1830. 



In R.-D.'s posthunious work (1863), which trcats of the Ca- 

 lypteratae in the sense of R.-D., and not in that of Macqnart, 

 the word Acalypteratae appears only once, in Vol. I, p. 81, and 

 this mention is evidently not due to R.-D., bnt is an Interpolation 

 of the Editor, based upon the erroneons assnmption of the identity 

 of the Calypteratae of R.-D. with the Calypteratae of Macquart. 

 The proof and explanation of this mistake, too long for Insertion 

 here, will be found in the Note II. 



In my sketch of R.-D.'s life (ßerl. E. Z. 1893, p. 385) I have 

 mentioned the antagonism which existed between R -D. and Mac- 

 quart. Macquart's publications were influenced by this antagonism. 

 In the Hist. Nat. des Dipt. II, p. 55 (1835) Macquart followcd 

 R.-D. in adopting his first family Calypteratae, but changed its 

 name into CreopMlae Latreille; he also adopted R.-D.'s Mesomydae, 

 which he called Anthomyzidae Latr. For the rest of the Muscidae 

 hc introduced, for the first time, the general name of Acalypteres 

 („Acalypterae Nob.", as he has it in the same work Vol. II, p. 354). 



This arrangcment is discussed in Westw. Introd. II, p. 566 (1840). 

 M eigen, when preparing his seventh, supplementär}', volume (1838) 

 was under the influence of Macquart') and accepted his three divi- 

 sions (Vol. VII, p. 172), I cannot make out, however, why he called 

 the first division Calypterae Macq. instead of Creophilae Latr., as 

 Macquart had it in 1835. Macquart may have advised him in 

 a letter. 



And indoed, in Macquart's Dipt. Exot. II, 3, p. 26—27 (1843) 

 WC tind the term Calyptcrees. But this tinic the Muscidae are 

 dividcd not into thrce, but into two divisions only, Calyptcrees 



') In 1839 Macquart visited Meigen and purcliased liis collection 

 for the Museum of Paris for 1200 francs. At the same time, hc ac- 

 quired, for the same Museum, two sfout quarto volumes containing 

 Moigen's colored drawings of all the species describcd by liini. Tlie 

 price paid was 1800 francs. Wliat becanie of these drawings, invaliiablc 

 for the identification of Meigen's descriptions? (Compare A. Förstur's 

 Biography of Meigen in the Stelt. Eiit. Z. 1846, p. 140,) 



